Caught that chap about to bring up adult fantasy (7)
I believe the answer is:
chimera
'up adult fantasy' is the definition.
'chimera' can be an answer for 'fantasy' (I've seen this before). I am unsure of the 'up adult' bit.
'caught that chap about to' is the wordplay.
'caught' becomes 'c' (cricket abbreviation).
'that chap' becomes 'him' (I've seen this in another clue).
'about to' becomes 'era' (I am not sure about this - if you are sure you should believe this answer much more).
'c'+'him'+'era'='CHIMERA'
'bring' acts as a link.
Can you help me to learn more?
(Other definitions for chimera that I've seen before include "Idle fancy" , "Mythological monster" , "eaders of radio appear after jingle" , "Mythical monster, part lion, goat and serpent" , "Illusory aim; monster" .)